Published online Feb 21, 2019. doi: 10.5492/wjccm.v8.i2.9
Peer-review started: December 13, 2018
First decision: January 5, 2019
Revised: January 24, 2019
Accepted: January 29, 2019
Article in press: January 30, 2019
Published online: February 21, 2019
In-hospital cardiac arrest (IHCA) portends a poor prognosis and survival to discharge rate. Prognostic markers such as interleukin-6, S-100 protein and high sensitivity C reactive protein have been studied as predictors of adverse outcomes after return of spontaneous circulation (ROSC); however; these variables are not routine laboratory tests and incur additional cost making them difficult to incorporate and less attractive in assessing patient’s prognosis. The neutrophil-lymphocyte ratio (NLR) is a marker of adverse prognosis for many cardiovascular conditions and certain types of cancers and sepsis. We hypothesize that an elevated NLR is associated with poor outcomes including mortality at discharge in patients with IHCA.
To determine the prognostic significance of NLR in patients suffering IHCA who achieve ROSC.
A retrospective study was performed on all patients who had IHCA with the advanced cardiac life support protocol administered in a large urban community United States hospital over a one-year period. Patients were divided into two groups based on their NLR value (NLR < 4.5 or NLR ≥ 4.5). This cutpoint was derived from receiving operator characteristic curve analysis (area under the curve = 0.66) and provided 73% positive predictive value, 82% sensitivity and 42% specificity for predicting in-hospital death after IHCA. The primary outcome was death or discharge at 30 d, whichever came first.
We reviewed 153 patients with a mean age of 66.1 ± 16.3 years; 48% were female. In-hospital mortality occurred in 65%. The median NLR in survivors was 4.9 (range 0.6-46.5) compared with 8.9 (0.28-96) in non-survivors (P = 0.001). A multivariable logistic regression model demonstrated that an NLR above 4.55 [odds ratio (OR) = 5.20, confidence interval (CI): 1.5-18.3, P = 0.01], older age (OR = 1.03, CI: 1.00-1.07, P = 0.05), and elevated serum lactate level (OR = 1.20, CI: 1.03-1.40, P = 0.02) were independent predictors of death.
An NLR ≥ 4.5 may be a useful marker of increased risk of death in patients with IHCA.
Core tip: Patients who have an in-hospital cardiac arrest (IHCA) event often have poor prognosis and their survival to discharge rates are dismal. Despite advancements in resuscitation, including the use of target temperature management, the prognosis for these patients has not improved over the past 30 years. Markers that are inexpensive and easy to use that may provide some prognostic information after an IHCA event are needed. A neutrophil-lymphocyte ratio greater than 4.5 may be a useful prognostic tool and marker for increased risk of death in patients with IHCA. In addition, older age, elevated serum lactate level were also independent predictors of death.